23566-23-6Relevant articles and documents
Novelties of selective triphasic synthesis of bis-(p-chlorobenzyl) sulfide using hydrogen sulfide and reusable phase transfer catalyst
Jha, Preeti,Mondal, Ujjal,Gogoi, Devipriya,Singh, Gaurav,Sen, Sujit
, p. 30 - 40 (2016)
The present investigation is based on the advancement in hydrogen sulfide (H2S) capture and utilization (HSCU). Commercially H2S is absorbed efficiently using alkanolamines such as methyldiethanolamine (MDEA). Aqueous H2S-rich MDEA is proposed to act as a sulfiding agent for aromatic halides such as p-chlorobenzyl chloride (p-CBC) to synthesize value-added thioethers. The objective of the present investigation is to synthesize bis-(p-chlorobenzyl) sulfide (BPCBS), a value-added thioether, selectively using p-CBC and H2S-laden aqueous MDEA. For the immiscible bi-phasic system, reusable solid phase transfer catalyst, polymer-bound tributylmethylammonium chloride (PBTBMAC) was employed under liquid-liquid-solid (L-L-S) mode in the presence of solvent toluene to enhance the reaction rate and product selectivity. Full conversion of p-CBC was obtained with 100% selectivity towards the desired product BPCBS at optimized specific level of process parameters. The catalyst has shown substantial activity even after three times of reuse, which leads to waste minimization and economic benefits. A generalized empirical kinetic model was developed and successfully validated against the experimental results. The triphasic reaction thus leads to process intensification, waste minimization and selectivity enhancement. The process can be utilized as an alternative to many other HSCU processes to utilize the sour gas in synthesizing value-added chemicals.
Nanolayered cobalt-molybdenum sulphides (Co-Mo-S) catalyse borrowing hydrogen C-S bond formation reactions of thiols or H2S with alcohols
Corma, Avelino,Sorribes, Iván
, p. 3130 - 3142 (2019/03/13)
Nanolayered cobalt-molybdenum sulphide (Co-Mo-S) materials have been established as excellent catalysts for C-S bond construction. These catalysts allow for the preparation of a broad range of thioethers in good to excellent yields from structurally diverse thiols and readily available primary as well as secondary alcohols. Chemoselectivity in the presence of sensitive groups such as double bonds, nitriles, carboxylic esters and halogens has been demonstrated. It is also shown that the reaction takes place through a hydrogen-autotransfer (borrowing hydrogen) mechanism that involves Co-Mo-S-mediated dehydrogenation and hydrogenation reactions. A novel catalytic protocol based on the thioetherification of alcohols with hydrogen sulphide (H2S) to furnish symmetrical thioethers has also been developed using these earth-abundant metal-based sulphide catalysts.
Indium-catalyzed reductive three-component coupling reaction of aliphatic/aromatic carboxylic acids with t-butyl mercaptan leading to unsymmetrical dialkyl sulfides
Sakai, Norio,Yoshimoto, Shunsuke,Miyazaki, Takahiro,Ogiwara, Yohei
supporting information, p. 3117 - 3120 (2016/07/06)
An InI3–TMDS (1,1,3,3-tetramethyldisiloxane) reducing system efficiently catalyzed a sequential three-component coupling of aliphatic carboxylic acids, aromatic carboxylic acids, and t-butyl mercaptan (t-butylthiol), to produce unsymmetrical dialkyl sulfides. With this reducing system, t-butyl mercaptan became a new source of sulfidation via an alkyl t-butyl sulfide that functioned as the reaction intermediate.
